海陆过渡相层序地层特征及其对页岩气储层的影响——以通许隆起中部太原组—山西组为例  

Sequential stratigraphic characteristics of marine-continent transitional sedimentary facies and the sequential influence on shale gas reservoirs--a case of Taiyuan-Shanxi formation sequence at central Tongxu uplift

作　　者：董果果 张馨元[1,2] 张栋 袁青松[1,2] DONG Guoguo;ZHANG Xinyuan;ZHANG Dong;YUAN Qingsong(Henan institute of geological survey, Zhengzhou 450001, China;Henan Industry and Technology Innovation Strategy Alliance of Underground Clean Energy Exploration and Development, Zhengzhou 450001, China)

机构地区：[1]河南省地质调查院,郑州450001 [2]地下清洁能源勘查开发产业技术创新战略联盟,郑州450001

出　　处：《地质找矿论丛》2021年第4期457-465,共9页Contributions to Geology and Mineral Resources Research

基　　金：国土资源部第二轮页岩气探矿权项目“河南中牟页岩气勘查”(编号:GT2012YQTKQCR0020);河南省重大科技专项项目“河南页岩气勘查开发及示范应用研究”(编号:151100311000);河南省国土资源厅科技攻关项目“河南省平原区晚古生代页岩气层岩相古地理研究”(编号:2015-1992-20)联合资助。

摘　　要：通许隆起二叠系发育一套海陆过渡相富有机质泥页岩,是近年来河南省页岩气勘探的重要领域。通过对区内钻井资料、海平面变化曲线、岩芯测试等资料的综合分析,以及对通许隆起中部太原组山西组页岩气层系开展层序地层的研究,初步分析了层序对页岩气储层发育的影响。可将区内目的层系划分出6个三级层序:SQ1、SQ2、SQ3位于太原组和山西组下部,主要为(灰)黑色泥页岩层序;SQ4、SQ5、SQ6位于山西组,主要为灰色泥页岩层序。其中,SQ1—SQ3中w(TOC)值与脆性矿物质量分数相对较高,泥页岩段w(TOC)值与海平面变化趋势呈正相关,脆性指数与海平面变化呈负相关;泥页岩孔隙度与渗透率,因受后期成岩作用和构造作用影响较大,与层序的相关性较差。综合研究表明,通许隆起中部东南方向SQ1—SQ3的海退体系域早期为页岩气勘探有利层位。A transitional marine-continent organic material-rich shale sequence is developed in Permian System at Tongxu uplift and it is now the key target for shale gas exploration in Henan province.Based on the analysis of drill data,global sea level change curve and data of drill cores,this paper deals with sequential stratigraphy of shale gas of Shanxi-Taiyuan formation sequence and roughly analyzes the influence of the sequential stratigraphy on the shale gas reservoir.The sequence is divided into 6 sub-sequences(SQ1,SQ2,SQ3,SQ4,SQ5,SQ6).The former three are grey black muddy shale located at Taiyuan formation and lower Taiyuan formation;the latter three,grey muddy shale at Shanxi formation.The w(TOC)value and mass fraction of brittle minerals of the sub-sequence SQ1-SQ3 are relatively higher.The w(TOC)value of the muddy shale is positively correlated to the change tendency of sea level,the mass fraction of brittle minerals negatively correlated to that of the sea level.Porosity and permeability of the muddy shale are largely influenced by tectonic activity and diagenesis and poorly correlated to the sequence.The comprehensive study shows that the early retrogression sedimentary system of SQ1-SQ3 in the southeast of the central Tongxu uplift is the favorable area to form shale gas reservoirs and the further exploration target.

关 键 词：通许隆起 页岩气 太原组 山西组 层序地层 河南省 

分 类 号：P618.13[天文地球—矿床学] TE132.2[天文地球—地质学]